Thalassemia is a dreaded disease among children. The disease is caused due to hereditary disorders connected with defective hemoglobin synthesis, characterised by hypochromia, microcytosis, haemolysis and a variable degree of anaemia. Thalassemia involves a heterogeneous group of molecular defects with a wide spectrum of clinical expressions.
Patients suffering from Thalassemia suffer from anaemias with decreased or absence of synthesis of a globin chain of a normal haemoglobin. The patients of thalassemia are broadly classified into two major groups according to the affected globin chain.
Alpha (.alpha.) Thalassemia is associated with decreased or absence of .alpha.-chain synthesis. Beta (.beta.) Thalassemia is associated with decreased or absence of .beta.-chain synthesis.
One may find also patients suffering from Thalassemia delta (.delta.) and Gamma (.gamma.) chain disorders, as well as those associated abnormal hemoglobin structure (e.g. Hb Lepose and Hb Constant Spring). These are rare and also contribute to the Thalassemia Syndromes.
The disease Thalassemia occurs world wide with a particular high incidence in the Mediterranean basin and in the South-East Asia. Malaria is also endemic in these areas--a significant fact since indirect evidence suggests that--Thalassemia (major) heteroxygosity confers protection against malaria.
The .beta.-Thalassemia or Thalassemia major type of the disease comprises a heterogeneous group of disorders usually characterised by absence of (.beta..degree.) or decreased (.beta.+) globin synthesis.
The type of .beta.-Thalassemia is also classified according to the severity of the anaemia. These clinical classifications serve to differentiate homozygous (Thalassemia intermedia or Thalassemia major) from heterozygous state (Thalassemia minima or Thalassemia minor). Though, it does not reflect genetic mutation, Thalassemia (minor) is a reduced rate of .beta.-globin synthesis, with an increased .alpha.-.beta. globin chains, but it is not like threatening.
Thalassemia (Major) also known as Cooley's anaemia, Mediterranean anaemia and Von-Jacksch's anaemia is characterised by marked anaemia (ranging from 1 to 6 gm/dl of homoglobin), severe hemolysis and ineffective erthropoiresis. The diagnosis is made in the 1st year of the life of the patient, often as early as 3 months. In the case of Thalassemia (Major), iron in the haemoglobin also breaks down and gets deposited in the vital organs of the body of the patients e.g. liver, kidney, spleen, heart etc. This is also known as iron overloading in the body and the life span of the child suffering from Thalassemia (major) becomes unpredictable. Every year out of 1,00,000 children born with Thalassemia (major) in the world, 10,000 are born in India.
The method which is available hitherto for the treatment of Thalassemia (major) is life long blood transfusions coupled with the taking of the drug called `Desferal` daily intermusculary. The chemical name of the drug is Deferoxamine Methane Sulphonate and the chemical formula is C.sub.28 H.sub.52 N.sub.4 O.sub.11 S.
Desferal is administered by injection and leads to the excretion of iron from the body of the patient through urinary excretion. It was found by medical profession that Desferal had many side effects like swelling of limbs, stiffness in joints and may inhibit tumor cell proliferation, parasite growth and the proliferation of the cerebral Malarial Parasite, Plasmodium Faliparum.
In addition, the above drug is to be injected daily under the skin of the patient in a controlled manner in such a way to avoid any side reaction causing allergic conditions. Such a treatment is highly painful. The treatment is also costly as the vial containing 500 mg of dry active substance will cost about US $10/-each.
Through a new oral iron chelating drug known as L-1, CP20, DMPH, Deferiprone (Chemical Name, 1,2, Dimethyl 3 Hydroxypyridine 4-one) has been reported very recently, it is yet to establish its potentiality of patients suffering from the disease of Thalssemia. The reported side effects of this drug are 1. Myelotoxicity i.e. occurance of neutropenia 2. Orthropathy i.e. skeleto-muscular pain and swelling around knee and hipjoints and lastly mild zinc defficiency occasionally leading to dermatopathy. (Reference may be made to the Proceedings of National Thalassemia Conference, 5-6 Feb., 1994, held in Delhi; L1: Oral Iron chelation Therapy-Indian Study by M. B. Agarwal). The cost of a capsule Deferiprone is approximately 50 U.S. cents (Rs. 12/-). A patient has to take 3-6 capsules per day. This will amount to US $70-90 (Rs. 1000-2000) per month.
Another method which is available for the treatment of the disease Thalassemia (major) is by the bone marrow transplantation (BMT). This is done by the taking the bone marrow of the matching donor and injecting it to the patient. The cost of such a treatment is around US $50000/-(Rs. 15,00,000/-). This is therefore beyond the reach of common man. Several treatments using bone marrow have been performed in many parts of the world including the U.S.A. and Italy. Recently, Christian Medical Colleage (Vellore), India and Appolo Hospital (Madras) India have also started this type of BMT treatment in India, but the cost is also on the higher side (Rs. 7 Lac. approx). Further, an increase in the life expectancy of these patients has yet to be established.
Under the prevailing present day conditions, regular blood transfusion and use of the drug `Desferal` by injection as explained above, is the best way to this dreaded disease. For the last decade, efforts are being made by medical profession throughout the world to find a treatment of this disease by a drug which will be low in cost and can be administered orally and have no side effects, but so far there has been no success.